Nowadays people wash hair everyday and casually perm or color. Hair damages physically or chemically caused by the hair wash, perm or color are serious problems. For damaged hair, conditioning is necessary. As a conditioning agent, oils, cationic surfactants, proteins and hydrolysates thereof, moisturizer, higher alcohols, and emulsions are used. However, conditioning effects of the oils, cationic surfactants, proteins and hydrolysates thereof, moisturizer, higher alcohols, and emulsions are lost by a hair wash and not durable.
To maintain effects of the conditioning, a hair treatment agent has been strongly desired which resists hair wash. As a method to maintain conditioning effects, Japanese Patent Application Laid-Open No. 2001-226236 discloses a method to treat the hair with a methylhydrogenpolysiloxane. The treatment with the polysiloxane is indeed effective but not sufficient. Moreover, unreacted Si—H bonds remain after the treatment, which sometimes cause generation of hydrogen gas. Thus, a hair treatment agent is desired which maintains hair conditioning effect.
Meanwhile, an organopolysiloxane represented by the formula (1)R1aR2bR3cSiO(4-a-b-c)/2  (1)is known from Japanese Patent Application Laid-Open No. 2001-72891.
The invention disclosed in the publication relates to a surface treatment of powder used for cosmetics with the organopolysiloxane. It is described that the surface treated powder is used for a hair cosmetic. However, the publication neither describes nor suggests applying the organopolysiloxane directly on the hair.